Redox Reactions And Electrochemistry Ques 748
Question: What will be the oxidation number of I in the $ KI_3 $ -
Options:
A) $ -\frac{1}{3} $
B) $ -\frac{1}{4} $
C) + 4
D) + 3
Show Answer
Answer:
Correct Answer: A
Solution:
[a] $ KI_3,\text{ }1+3\times ( a )=0 $ $ a=-\frac{1}{3} $ or $ KI_3, $ is $ KI+I_2 $
$ \therefore $ I has two oxidation no. - 1 and 0 respectively. However factually speaking oxidation number of I in $ KI_3 $ is an average of two values - 1 and 0. $ \text{Average O}\text{.N}\text{.}=\frac{-1+2\times ( 0 )}{3}=-\frac{1}{3}. $
